Analysis of MYRF gene variant in a fetus with Cardiac-urogenital syndrome / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a fetus with Cardiac-urogenital syndrome (CUGS).@*METHODS@#A fetus with congenital heart disease identified at the Maternal Fetal Medical Center for Fetal Heart Disease, Beijing Anzhen Hospital Affiliated to Capital Medical University in January 2019 was selected as the study subject. Clinical data of the fetus was collected. Copy number variation sequencing (CNV-seq) and trio-whole exome sequencing (trio-WES) were carried out for the fetus and its parents. Candidate variants were verified by Sanger sequencing.@*RESULTS@#Detailed fetal echocardiographic examination had revealed hypoplastic aortic arch. The results of trio-WES revealed that the fetus has harbored a de novo splice variant of the MYRF gene (c.1792-2A>C), for which both parents were of the wild-type. Sanger sequencing confirmed the variant to be de novo. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was rated as likely pathogenic. CNV-seq has identified no chromosomal anomalies. And the fetus was diagnosed with Cardiac-urogenital syndrome.@*CONCLUSION@#The de novo splice variant of the MYRF gene probably underlay the abnormal phenotype in the fetus. Above finding has enriched the spectrum of MYRF gene variants.

Genetic etiology of fetal conotruncal defects and significance of copy number variation sequencing and whole exome sequencing: analysis of 196 cases / 中华围产医学杂志

Objective:To investigate the genetic etiology of fetal conotruncal heart defects (CTDs) and to evaluate the performance of copy number variation sequencing (CNV-seq) and whole exome sequencing (WES) in identifying the genetic etiology.Methods:This retrospective study involved 196 fetuses diagnosed with CTDs by fetal echocardiography in Beijing Anzhen Hospital, Capital Medical University from June 2017 to December 2021. CNV-seq was performed to screen for chromosomal abnormalities [aneuploidy and copy number variations (CNVs)] in the fetuses and their parents, and then WES was performed if CNV-seq was negative. The diagnostic yields of genetic abnormalities [aneuploidy+CNVs+single nucleotide variations (SNVs)] for different types of CTDs were compared using Chi-square test. Results:CNV-seq revealed 54 cases (27.6%, 54/196) with chromosomal abnormalities, including 14 (7.1%, 14/196) aneuploidies, 39 (19.9%, 39/196) CNVs and one aneuploidy complicated by CNVs. Together with another 13 fetuses with pathogenic or likely pathogenic SNVs detected by WES among the rest 142 cases whose CNV-seq results were negative, the total detection rate of genetic abnormalities was 34.2% (67/196). WES increased the diagnostic yield for CTDs by 9.2% (13/142). There was significant difference in the diagnostic yields for different types of CTDs ( χ2=20.31, P=0.002). The diagnostic yield was relatively high for interrupted aortic arch of type B, absent of the pulmonary valve -type of tetralogy of Fallot (9/10 and 8/12), but low for transposition of the great arteries (12.5%, 5/40). Conclusions:CNVs are the common genetic abnormalities in fetal CTDs, and SNVs are also detected in some cases. It is recommended that all fetuses with CTDs should undergo genetic testing. CNV-seq should be used in combination with WES if possible to improve the identification of genetic etiology and provide reference for genetic counseling.

Nonsense variation of OTUD5 gene in a fetus with X-linked multiple congenital anomalies- neurodevelopmental syndrome / 中华围产医学杂志

We report a fetus presented with complex cardiac malformations, pulmonary atresia with ventricular septal defect, detected by fetal echocardiography at 17 +4 weeks. The pregnancy was terminated after routine counseling and genetic tests were performed on umbilical cord of the induced fetus and peripheral blood samples of the parents. Whole-exome sequencing identified a novel maternally-inherited and likely pathogenic variation hemizygous nonsense variant, c.1651C>T (p.Gln551*) in the OTUD5 gene (NM_017602.3), which was confirmed by subsequent Sanger sequencing. The fetus was finally diagnosed as X-linked multiple congenital anomalies-neurodevelopmental syndrome.

Pathogenesis, prenatal diagnosis and clinical features of fetal cardiomyopathies / 中华超声影像学杂志

Objective:To summarize the etiological mechanism, echocardiographic and clinical features of fetal cardiomyopathies (FCMs).Methods:According to the data of echocardiography in Maternal-Fetal Medicine Center in Fetal Heart Disease of Beijing Anzhen Hospital during 2015 January to 2020 December, 70 cases with FCMs were retrospectively reviewed, and the clinical, ultrasonic, pathological and clinical outcome data were collected. Whole exome sequencing and whole genome sequencing were used to identify the genetic changes.Results:Primary FCMs were diagnosed in 55 cases (78.6%, 55/70), including 39 fetuses with non-compaction of the ventricular myocardium (NVM), 10 with dilated cardiomyopathy (DCM), 5 with hypertrophic cardiomyopathy (HCM), and 1 with restricted cardiomyopathy (RCM). Secondary FCMs were diagnosed in 15 cases (21.4%, 15/70), including 7 fetuses with maternal anti-Ro/La antibodies (presenting with DCM), 4 with twin-twin transfusion syndrome (2 with DCM and 2 with HCM), 2 with fetal anemia (presenting with DCM), 1 with maternal diabetes (presenting with HCM) and 1 with chorioangioma of the placenta (presenting with DCM). In all cases, 9 cases were born, 3 cases died in perinatal period, and 58 pregnancies were terminated due to ineffective treatment or the decisions of pregnant women. Thirty cases with primary FCMs were performed with genetic tests, and 13 of them were identified with positive genetic changes related to FCMs, including 12 cases with NVM and 1 with HCM.Conclusions:Primary FCMs are more common than secondary FCMs in fetal period. The genetic disorders have a high proportion in fetal NVM. Fetal DCM and HCM have a large spectrum of intrinsic and extrinsic causes.

Echocardiographic and pathological features of fetal Kabuki syndrome / 中华围产医学杂志

Objective:To summarize the echocardiography and pathological features of fetal Kabuki syndrome.Methods:This study retrospectively analyzed the echocardiography and pathological features of seven fetuses with KMT2D pathogenic variants confirmed by copy number variation sequencing, and who were identified as complex congenital heart disease by fetal echocardiography, at Beijing Anzhen Hospital, Capital Medical University and other multi-center collaborative hospitals on fetal congenital heart diseases from January 2013 to May 2018. All the seven fetuses were artificially aborted. Descriptive statistics were used for data analysis. Results:(1) The seven pregnant women aged 29 (27-32) years and had an abortion at 23 (22-25) gestational weeks. There were three male and four female fetuses. (2) Pathogenic mutations in KMT2D gene were detected in all seven cases, including one nonsense mutation and six frameshift mutations. (3) All fetuses had left heart obstruction with or without aortic arch dysplasia/interruption of the aortic arch. There were three with hypoplastic left heart syndrome, two with a single ventricle, one with aortic atresia, and one with severe mitral valve dysplasia. Other cardiovascular abnormalities included aortic arch branch abnormalities, double-outlet of the right ventricle, ventricular septal defect, tricuspid atresia, pulmonary valve stenosis (nearly atresia) complicated by pulmonary dysplasia, persistent left superior vena cava, and patent or closed foramen ovale. Secondary changes included enlargement of the right atrium and right ventricle, and dilatation of the pulmonary artery or ductus arteriosus. (4) Four of the seven fetuses showed multiple extracardiac system abnormalities, including facial deformities (two cases), pulmonary dysplasia (two cases), digestive abnormalities(two cases), and urogenital system abnormalities (two cases). Conclusions:The main features of echocardiography for fetal Kabuki syndrome are left heart obstruction, often complicated by other congenital cardiovascular abnormalities.

Fetal echocardiographic features and clinical phenotype of 22q11.2 microdeletion syndrome: analysis of 46 cases / 中华围产医学杂志

Objective:To investigate the fetal echocardiographic features and clinical phenotype of 22q11.2 microdeletion syndrome (22q11.2DS) and provide information for the diagnosis of fetal 22q11.2DS.Methods:We retrospectively retrieved information of 822 fetuses, who were diagnosed with congenital heart disease by fetal echocardiography, with results of low-coverage whole genome sequencing from the Genetic Database of Beijing Key Laboratory of Fetal Heart Disease and Maternal Fetal Medicine Research from January 2013 to April 2019. Phenotype, fetal echocardiographic features and genetic origin results of 46 fetuses with 22q11.2DS (22q11.2DS group) were summarized. Another 68 fetuses who were negative for 22q11.2DS but had conotruncal defects(CTD) were selected as control. Differences in fetal cardiac axis were compared between the two groups. Independent samples t test and Chi-square test were used for statistical analysis. Results:22q11.2DS was detected in 46 fetuses giving a total detection rate of 5.60% (46/822). The detection rates of 22q11.2DS in fetuses with CTD and non-CTD were 14.8% (45/305) and 0.2% (1/517), respectively ( χ2=74.253, P<0.001). Fetal cardiac axis was left-deviated in those with 22q11.2DS compared with those of the control [(61.7±15.3)°vs (55.7±13.4)°, t=-3.843, P=0.001]. Conclusions:CTD are the common clinical phenotypes of fetal 22q11.2DS. Fetal 22q11.2DS should be considered and the corresponding prenatal genetic diagnosis is highly suggested when the fetus is diagnosed with CTD especially combined with an enlarged cardiac angle.

Fetal Smith-Magenis syndrome diagnosed after pregnancy termination by low-coverage whole-genome sequencing: a report of two cases / 中华围产医学杂志

We reported two fetal cases diagnosed with Smith-Magenis syndrome.One case was found with bilateral ventriculomegaly,double-outlet right ventricle,pulmonary stenosis and ventricular septal defect when performing fetal echocardiography.Then the fetus was diagnosed with severe tetralogy of Fallot and tortuous ductus arteriosus by autopsy.The other case was suggested to have tetralogy of Fallot,right aortic arch and ectopic ductus arteriosus by fetal echocardiography,which was later confirmed by autopsy.Both of the two pregnancies were terminated.Tissue samples of the two fetuses were analyzed by the low-coverage whole-genome sequencing,and both cases carried a microdeletion of 3.63 Mb and 4.86 Mb in chromosome 17pl 1.2,which overlapped with the missing segments causing Smith-Magenis syndrome.Therefore,the two fetuses were both diagnosed with Smith-Magenis syndrome.

Fetal pulmonary atresia with ventricular septal defect :echocardiographic findings ,associated anomalies and chromosomal characteristics / 中华超声影像学杂志

Objective To analyze the echocardiographic findings , associated anomalies and chromosomal characteristics in fetuses with pulmonary atresia with ventricular septal defect ( PA/VSD ) . Methods T he echocardiographic data and follow‐up materials were retrospectively reviewed in 30 256 fetuses from December 2012 to M arch 2018 in the consultation center of fetal heart disease in maternal‐fetal medicine in Anzhen hospital . Of all the fetuses ,59 cases ( 0 .19% ) had PA/VSD . T he echocardiographic findings ,associated anomalies and chromosomal characteristics were retrospectively analyzed in all the 59 fetuses with PA/VSD . Based on w hether the presence of the native pulmonary arteries and the major aortopulmonary collateral arteries ( M APCAs) or not ,the PA‐VSD was classified into type A ,type B ,and type C . Results A large ventricular defect was demonstrated in five‐chamber view with 61 .7% of the mean ratio of the aortic overriding . O ther fetal echocardiographic features of all the 59 fetuses with PA/VSD included :the right aortic arch ( n ＝19 ) ,reversal flow in the ductus arteriosus ( n ＝40 ) ,M APCAs ( n ＝24) . T he classification of the PA/VSD included :type A ( n ＝35) ,type B ( n ＝5) and type C ( n ＝19) . Associated anomalies :persistent left superior vena cava ( n ＝ 13 ) ,anomalous pulmonary vein connection ( n＝5 ) ,complete atrioventricular septal defect ( n ＝ 5 ) ; single umbilical artery ( n ＝ 3 ) ,right atrial isomerism ( n ＝3) . Of all the 30 cases performed chromosomal test ,3 cases had aneuploidy and 7 cases had microdeletion of chromosome . Conclusions The fetal echocardiographic findings of the PA/VSD are characteristic . For prenatal diagnosis of PA/VSD ,the type of PA/VSD should be defined and chromosomal test should be performed ,w hich can be helpful for prenatal consulting .

Study on the FBN1 gene mutation spectrum and association between genotype and clinical phenotype in 300 Marfan syndrome patients and their relatives / 中华胸心血管外科杂志

Objective To investigate the correlations between the FBN1 gene mutation types and the clinical phenotype . Methods 87 probands with Marfan or Marfan-like syndromes and their family members were enrolled in this study ( total 300 cases).The clinical manifestations of each patients involving the ocular, cardiovascular system, skeletal system and other im-plicated systems were collected and evaluated .According to the clinical manifestations , these patients were divided into two groups, namely aortic dissection group and aortic root aneurysm group.Blood samples were taken from patients and DNA se-quencing was performed on each patient by the genetic aortic disease gene Panel .The detected single nucleotide variants ( SNVs)/indel were interpreted according to the ACMG guidelines, and the pathogenic variation was confirmed through Sanger sequencing.The aortic wall tissue was obtained from MFS patients who underwent surgery .The correlations between genotypes and clinical phenotypes were further explored by comparing the aortic wall tissue histological specimens of each genotype pa-tient.Results A total of 92 FBN1 mutations(31％) were detected in 300 people with Marfan syndromes or Marfan-like syn-dromes, 18 of which were undiscovered mutations.There were 49 missense mutations(53.26％), 13 splicing mutations (14.13％), 17 frameshift mutations(18.48％), and 13 nonsense mutations(14.13％).In this cohort, 24 cases had aortic dissection and 25 cases were aortic root aneurysm.Statistical analysis revealed that patients with aortic dissection mostly ap-peared in frameshift mutations(29.17％ vs.4.00％, P =0.017).However, patients with aortic root aneurysm mostly ap-peared in missense mutations(72.00％ vs.37.50％, P =0.015), and accompanied with ectopia lentis(41.67％ vs. 8.33％, P=0.008).Pathological specimens staining found that elastic fibers in the aortic wall of patients with frameshift mu-tations are sparser, and the smooth muscle cells are more deficient and more disorganized than patients with missense muta-tions.Conclusion FBN1 gene frameshift mutations result a lack of elastic fibers and disorganized smooth muscle cells in aor-tic wall and are presented more in patients with aortic dissection than aortic root aneurysm .

Preliminary exploration of genotype-phenotype correlation in chinese with hypertrophic cardiomyopathy / 中华胸心血管外科杂志

Objective To explore the genetic mutation spectrum of patients with hypertrophic cardiomyopathy (HCM) and analysis the correlation of genotype phenotype.Methods Collect peripheral venous blood of the 51 cases unrelated HCM patients(35 male and 16 female) in the Beijing Anzhen Hospital of Capital Medical University from 2013 to 2016.Sequence whole exons of human and analysis seven major mutations of HCM including:MYBPC3、MYH7 、TNNT2、TNNI3 、MYL2 、TPM1 and ACTC1.Then compare the results with clinical characteristics.Results 24 patients(47.1％) had 22 kinds of pathogenicity or possibly pathogenicity mutations.The 90.9％ (20/22) of mutations only occurred one time,except MYH7 gene's 663 amino acid and the TNND gene's 157 amino acid which had twice.The mutations of MYBPC3,MYH7,TNNT2,TNNI3,MYL2,TPM1 and ACTC1 accounted for 45.8％ (11/24),20.8％ (5/24),12.5％ (3/24),8.3％ (2/24),8.3％ (2/24),4.2％ (1/24),and 0 respectively.No amphimutation had been found that causes illness or possibly.Through the comparison of clinical features between Genotype positive(24 cases) and negative(27 cases) patients:the incidence of syncope(19.6％ vs.7.8％,P ＜ 0.05),the largest left ventricular wall thickness[(22.8 ± 2.6) mm vs.(20.0 ± 3.4) mm,P ＜ 0.05],family history of HCM(20.8％ vs.0,P ＜0.05),percentage of apical hypertrophy(25.5％ vs.11.8％,P ＜ 0.05);The ratio of left ventricular outflow tract obstruction in MYH7 group was higher than MYBPC3 group (80.0％ vs.18.2％,P ＜ 0.05).Conclusion MYBPC3 is the most common mutation gene in HCM patients.Phenotype is more severe in geuotype positive patients than in genotype negative patients.Relationship between specific gene mutations and clinical phenotype requires further study.

Analysis of chromosomal abnormalities in 107 fetuses with conotruncal defects using low coverage whole-genome sequencing / 中华围产医学杂志

Objective To investigate chromosomal abnormalities in fetuses with conotruncal defects(CTD).Methods From January 2013 to February 2017,107 fetuses (singleton pregnancy) prenatally diagnosed as CTD in Beijing Anzhen Hospital were enrolled.Umbilical cord specimens of these fetuses were collected after termination of pregnancy and analyzed by low coverage whole gene sequencing to detect chromosomal aneuploidy and copy number variations.Types of chromosomal abnormalities in these cases were analyzed.Chi-square test was used for statistical analysis.Results Twenty-two cases (21％,22/107) were identified with chromosomal abnormalities.The most common seen chromosomal abnormalities were found in those with interrupted aortic arch (2/2),followed by those with tetralogy of Fallot and pulmonary atresia/stenosis accompanied with ventricular septal defect (28％,12/43).No chromosomal abnormalities were detected in fetuses with aortopulmonary septal defect (0/2).Differences were shown in the detection rates of chromosomal abnormalities among different types of CTD (x2=12.744,P=0.026).Among the 22 fetuses with chromosomal abnormalities,there were seven with abnormal aneuploidy (three trisomy-13s,two trisomy-18s,one trisomy-21 and one 45,X) and 15 with pathogenic copy number variations [11 cases with 22q11.2 microdeletion syndrome,two with 17p12p11.2 microdeletion (Smith-Magenis syndrome),one with 8p23.3p21.3 microduplication and one with 2p23.1p25.2 microdeletion].Of the 15 cases with pathogenic copy number variations,12 segments of microdeletion/microduplications were de novo and one was paternally inherited,while the causes of the other two were not clear because their parents refused chromosomal testing.Conclusions Fetal CTD are likely to be accompanied with aneuploidy abnormalities and chromosome microdeletions/microduplications and the detection rate of chromosomal abnormalities varied with the type of CTD.Microdeletion and microduplication,especially de novo microdeletions/duplications,are the common chromosomal abnormalities.Chromosome analysis is recommended for fetuses prenatally diagnosed with CTD.